Many types of wellbore treatment require the selective communication of fluids from the surface to a particular zone of a well. One type of wellbore treatment, hydraulic fracturing, is a common and well-known enhancement method for stimulating the production of hydrocarbon bearing formations. The process involves injecting fluid down a wellbore at high pressure. The fracturing fluid is typically a mixture of a transport fluid such as water or diesel, various chemicals to treat the well or to enhance the ability of the transport fluid to entrain the proppant, and proppant. The proppant may be made of natural materials or synthetic materials.
Generally the fracturing process includes pumping the fracturing fluid from the surface through a tubular. The tubular has been prepositioned in the wellbore to access the desired hydrocarbon formation. Depending upon the wellbore environment and the requirements of the operators the well may be either cased or uncased. Packers may be deployed to seal the tubular both above and below each formation or formation zone to isolate fluid flow along the tubular and force the fluid either into or out of the desired formation or formation zone while preventing unwanted fluid loss. Pressure may then be provided from the surface to the desired hydrocarbon formation in order to open a fissure or crack in the hydrocarbon formation.
In the past many types of packers have been used for zonal isolation in a wellbore such as inflatable packers, swell packers, and solid body packers. Each type of packer has its limitations.